全文获取类型
收费全文 | 126392篇 |
免费 | 732篇 |
国内免费 | 510篇 |
专业分类
化学 | 44989篇 |
晶体学 | 1973篇 |
力学 | 8617篇 |
综合类 | 48篇 |
数学 | 27358篇 |
物理学 | 44649篇 |
出版年
2023年 | 113篇 |
2022年 | 237篇 |
2021年 | 238篇 |
2020年 | 218篇 |
2019年 | 204篇 |
2018年 | 9945篇 |
2017年 | 10901篇 |
2016年 | 4854篇 |
2015年 | 1288篇 |
2014年 | 643篇 |
2013年 | 1042篇 |
2012年 | 5759篇 |
2011年 | 14987篇 |
2010年 | 8845篇 |
2009年 | 8952篇 |
2008年 | 12718篇 |
2007年 | 16560篇 |
2006年 | 1300篇 |
2005年 | 8420篇 |
2004年 | 4573篇 |
2003年 | 4350篇 |
2002年 | 2121篇 |
2001年 | 1152篇 |
2000年 | 1013篇 |
1999年 | 620篇 |
1998年 | 437篇 |
1997年 | 413篇 |
1996年 | 500篇 |
1995年 | 376篇 |
1994年 | 355篇 |
1993年 | 294篇 |
1992年 | 294篇 |
1991年 | 271篇 |
1990年 | 263篇 |
1989年 | 237篇 |
1988年 | 218篇 |
1987年 | 212篇 |
1986年 | 177篇 |
1985年 | 188篇 |
1984年 | 179篇 |
1983年 | 148篇 |
1982年 | 137篇 |
1981年 | 131篇 |
1980年 | 120篇 |
1979年 | 137篇 |
1978年 | 141篇 |
1976年 | 100篇 |
1975年 | 85篇 |
1973年 | 116篇 |
1968年 | 113篇 |
排序方式: 共有10000条查询结果,搜索用时 140 毫秒
1.
Tian Xiu-Zhi Yang Rui Ma Jia-Jia Ni Yong-Hao Deng Hai-Bo Dai Lei Tan Jiao-Jun Zhang Mei-Yun Jiang Xue 《高分子科学》2022,40(7):789-798
Chinese Journal of Polymer Science - Antistatic and strength properties are of vital importance for polyurethane rubber used in moving parts of many industrial instruments. Herein, polyurethane was... 相似文献
2.
Li Y. Shi W. H. Dong L. M. Xu S. X. Huang H. J. Yin J. R. 《Journal of Applied Spectroscopy》2022,89(3):534-541
Journal of Applied Spectroscopy - Sr3B2O6:Dy3+, Eu3+ single-matrix white-light-emitting materials are prepared using the high-temperature solid-state method. The microstructure, emission spectrum,... 相似文献
3.
Atopic dermatitis is characterized by leukocyte migration into the skin dermis and typically driven by excessive chemokine production at the site of inflammation. Conventional topical formulations such as gels, creams, and ointments are insufficient for this treatment because of low penetration of drug molecules into the targeted skin tissues. Herein, using a simple, green, sustainable strategy, we have developed novel primary zein nanoparticles embedded in curcumin (Cur) and coated with silk sericin (ZHSCs) for the topical delivery of Cur to penetrate into the dermis and exercise anti-dermatitis effects on the lesion with minimal side-effects. Transdermal delivery experiments and porcine skin fluorescence imaging indicated that ZHSCs facilitate the penetration of Cur across the epidermis layer of skin to reach deep-seated sites. Notably, ZHSCs = 1:0.25 (zein-to-silk sericin mass ratios of 1:0.25) markedly elevated the skin permeability and cumulative turnover of Cur transferred, which were provided a greater than a 3.8-fold increase relative to free Cur. The special nanoparticles of ZHS = 1:0.25 possessed the deepest localization depth and experience a transition of the particle structure and core-shell separation after penetrating into the dermis of skin. In a cell model of dermatitis induced by tumor necrosis factor α/interferon γ co-stimulation, compared with free Cur, Cur-loaded ZHS nanoparticles down-regulated the generation of inflammatory cytokines and chemokines in keratinocytes through suppression of the nuclear translocation of NF-κBp65 and hence exerted an anti-dermatitis effect. This strategy may provide new avenues and direction for the demanding issues of valid topical delivery systems. 相似文献
4.
K. E. Prikhodko M. M. Dementyeva B. A. Gurovich D. A. Komarov L. V. Kutuzov 《Crystallography Reports》2018,63(2):241-244
The change in the free-electron density in ultrathin (5 nm) superconducting NbN films in the initial state and after irradiation by O+ ions to doses of (0.1–0.9) × 1017 cm–2 has been studied by electron energy-loss spectroscopy (EELS). The analysis has been performed on cross section samples prepared by the focused ion beam method, using plasmon oscillations with energies up to 50 eV. The radiation-induced replacement of nitrogen atoms with oxygen atoms in niobium nitride is found to change the electrical properties of the material, which leads to a decrease in the free-electron density with an increase in the irradiation dose. 相似文献
5.
6.
7.
8.
9.
10.
Analysis and pharmacokinetic study of polyphyllin H in beagle dog plasma after oral administration of Rhizoma Paridis Extracts by LC‐MS/MS 下载免费PDF全文